Institute for Communication Technologies and Embedded Systems

Brightening the Optical Flow through Posit Arithmetic

Authors:
Saxena, V. ,  Reddy, A. ,  Jonathan, N. ,  Gustafson, J. L. ,  Sangeeth, N. ,  Leupers, R.Merchant, F.
Book Title:
International Symposium on Quality Electronic Design (ISQED)
Date:
Apr. 2021
DOI:
10.1109/ISQED51717.2021.9424360
hsb:
RWTH-2021-08750
Language:
English
Abstract:
As new technologies are invented, their commercial viability needs to be carefully examined along with their technical merits and demerits. The emph{posit}textsuperscript{TM} data format, proposed as a drop-in replacement for IEEE 754textsuperscript{TM} float format, is one such invention that requires extensive theoretical and experimental study to identify products that can benefit from the advantages of posits for specific market segments. In this paper, we present an extensive empirical study of posit-based arithmetic vis-`a-vis IEEE 754 compliant arithmetic for the optical flow estimation method called Lucas-Kanade (LuKa). First, we use emph{SoftPosit} and emph{SoftFloat} format emulators to perform an empirical error analysis of the LuKa method. Our study shows that the average error in LuKa with SoftPosit is an order of magnitude lower than LuKa with SoftFloat. We then present the integration of the hardware implementation of a posit adder and multiplier in a RISC-V open-source platform. We make several recommendations, along with the analysis of LuKa in the RISC-V context, for future generation platforms incorporating posit arithmetic units.
Download:
BibTeX